This disclosure relates generally to optoelectronic components and more particularly to a vertical light emitting diode (VLED) die, and method of fabrication.
An optoelectronic system, such as a light emitting diode (LED), can include one or more light emitting diode (LED) dice mounted to a substrate. One type of light emitting diode (LED) die, known as a vertical light emitting diode (VLED) die, includes a multi-layer semiconductor substrate made of a compound semiconductor material, such as GaN. The semiconductor substrate can include a p-type confinement layer having p-type dopants, an n-type confinement layer having n-type dopants, and a multiple quantum well (MQW) layer located between the confinement layers configured to emit light.
The vertical light emitting diode (VLED) die can also include an electrode on the n-type confinement layer, and a mirror in contact with the p-type confinement layer. The electrode provides current to the n-type confinement layer for activating the multiple quantum well (MQW) layer to emit light. The mirror reflects the emitted light outward. One problem with this type of vertical light emitting diode (VLED) die is that current can accumulate on specific areas of the n-type confinement layer, particularly near the electrode, limiting the efficiency of the multiple quantum well (MQW) layer. This problem, which is sometimes referred to as “current crowding”, requires higher forward bias (Vf), and also increases power consumption and heat output. One prior art approach to this problem is to form the electrode with a number of legs that spread out the current. However, this approach tends to cover a large area of the multiple quantum well (MQW) layer limiting brightness.
The present disclosure is directed to a vertical light emitting diode (VLED) die having an electrode frame and to a method for fabricating the vertical light emitting diode (VLED) die. The vertical light emitting diode (VLED) can be used to construct light emitting diodes (LED) having improved thermal and electrical characteristics.